Portable radio frequency (RF) receivers are usually worn on one's belt or in one's shirt pocket. Such receivers are commonly called pagers and either emit an alerting tone, thereby informing the wearer to perform some prearranged act, or reproduce a voice message. When the possessor of such a receiver is in a vehicle, the sensitivity of the receiver deteriorates substantially primarily because of all the metal surrounding the receiver. Also, the receiver is difficult to hear and perhaps uncomfortable when worn on one's person when sitting in the vehicle.